Fig. 3. (A–D) Normalized photoluminescence spectra of symmetric controls (A) TRZ–TRZ 1 and (B) DPA–DPA 2, alongside asymmetric donor–acceptor cyclophanes (C) DPA–TRZ 4 and (D) DPA–CN 5 in five representative solvents. 1 and 2 exhibit monochromatic emission, whereas 4 and 5 display bimodal solvatochromism in solvents of intermediate polarity. (E–H) Corresponding Lippert–Mataga plots correlating the Stokes shift (Δν) to the solvent orientation polarizability (Δf) across the complete 16-solvent series. While 1 (E) and 2 (F) demonstrate a single emissive state with minor solvent dependence the asymmetric compounds 4 (G) and 5 (H) resolves into two distinct linear correlations: a LE state (blue) whose shallow slope mirrors the symmetric controls, and a highly polar CT state (red) exhibiting a steep positive slope.
